Lets deal with reductionism. In some quarters it seems to have a bad name. To me it is one of the corner stones of the confidence in science.
Conventionally, we have the physical sciences, mainly physics and chemistry, that examine the basics of matter and energy, space and time. The findings should be universally applicable to everything except spooking spiritual non-material stuff. On top of this we have (my personal name) the historic sciences, mainly geology, biology and astronomy, that examine how things came to be the way they are at any time and place. They use the ‘laws’ and ‘theories’ of the physical sciences as the foundations for their own ‘theories’. In this sense the historical sciences’ theories can be reduced to those of physics and chemistry. This does not mean that a geologist is going to explain volcanos in terms of protons and electrons – but they know that if they worked the years it would take, they could do it. Sciences are looking for foundational theories that cover their area. So physics has quantum theory and the theory of relativity (which they want to connect in one theory). Plate tectonic theory is almost central to geology; biology rests largely on the theory of evolution. Each of these sciences has its specialty areas, like molecular biology with their own theories; molecular biology can be reduced to biology and chemistry. These theories are convincing because of the experimental evidence and because they can be reduced to physical sciences.
I know there are other sciences such as the applied sciences like medicine that lean on other sciences. And there are non-sciences that science uses as tools such as mathematics. Nothing is as simple as this little picture implies. I am not trying to draw a picture of the sciences but of the principal of reductionism.
Reductionism does not mean taking the world apart and not putting it back together – things are not left thrown about on the floor. It is not the opposite of holistic thinking – science very often looks at the big picture. Reductionism is the insurance policy that thought has not flown away from the solid ground of the physical world and that different as the various sciences are, they are not incompatible.
This is why the phrase ‘emerging properties’ bothers me. It is one thing to say, “here is the evidence but it has not yet been reconciled with some other parts of science.” It is often an honest statement of the state of affairs. But to say that something is an emerging property is not clear. It is used often as an explanation although it explains nothing but it does imply that reduction might be impossible. Sometimes it seems to mean that the evidence appears to show a material situation but I would like to leave open a non-material situation. Or vice versa, it looks non-material but I would like to leave open the possibility that it is material. It is sitting of the fence be refusing to say that the state of reduction actually is in this case.
There is another idea that bothers me. It is that there is a material world with no dualism or magic non-material stuff ; BUT, there are two ways to describe it that are not connected by reduction. What? There are psychological/mental explanations and scientific/biological explanations of the same things. It is not the reality that is dualist but the description of reality. This is like saying that psychology is not a science and never will be. That is not what many psychologists want.
I, for one, cherish reduction as an ideal in science. In Christof Koch book, Consciousness: Confessions of a Romantic Reductionist, he says he is a reductionist because, “I seek quantitative explanations for consciousness in the ceaseless and ever-varied activity of billions of tiny nerve cells, each with their tens of thousands of synapses; romantic, because of my insistence that the universe has contrails of meaning that can be deciphered in the sky about us and deep within us”